The present invention relates to a portable smart card reader assembly serving to provide connection between an electronic smart card and a further electronic device, e.g. a reader of the kind as used for PCMCIA type cards
The term xe2x80x9csmart cardxe2x80x9d is used below to designate cards of essentially rectangular shape, such as bank cards, prepayment cards for public telephones, pay TV services, security cards or personal authentication cards. The format of such cards is standardized and each of them carries an array of contact pads which is situated at a specific predefined location on the main surface of the card and is connected with other electronic circuitry for performing respective electronic operations.
In computers, especially personal computers, lap- or palmtops it is becoming increasingly common to use electronic PCMCIA plug-in cards having a similar format as a smart card but of greater thickness. This type of card has been standardized by the xe2x80x9cPersonal Computer Memory Card International Associationxe2x80x9d (PCMCIA), and in particular many desk top and nearly all portable computers, include a PCMCIA type card reader. The term xe2x80x9cPCMCIA cardxe2x80x9d is used below not only for all cards that do indeed comply with the PCMCIA standard, but also for any similar cards that are substantially rectangular in shape, and that are terminated at one end by a connector mateable with the male connector of the PCMCIA card reader. Further, the term xe2x80x9creaderxe2x80x9d is not limited here to an electronic device performing a read operation but shall also cover any read and/or write devices.
Special card readers are known that are capable of reading both smart cards and PCMCIA type cards. Such readers generally include an adapter enabling them to adapt to the differences of card thickness, and also two different types of electrical connector, i.e. PCMCIA type and smart card type. By way of example, this type of reader is described in French patent application FR 2 687 238 and U.S. Pat. No. 5,198,645.
Another solution described in European patent application EP 0 552 078 consists of reducing the thickness of a PCMCIA card and in fitting an additional connector with flush contacts on its main face.
A still further solution is proposed by U.S. Pat. No. 5,296,692 which describes an adapter capable of being inserted into a reader. The adapter includes a receptacle that can receive a PCMCIA type card and a smart card, the cards being positioned one above the other. This results in the slot through which the cards are inserted being of greater width than the slot of a conventional card reader so that the adapter does not have standard dimensions and cannot be used directly with an ordinary PCMCIA type card reader.
U.S. Pat. No. 5,548,485 teaches a cover assembly for IC cards is known where a soldering and spot welding techniques are adopted for mounting of different parts of the assembly. However, often hybrid circuitry and surface mounted components are vulnerable to external heat and are not apt to be incorporated in a housing as described in this document.
U.S. Pat. No. 5,673,180 describes a case for a handheld microcircuit card reader. According to this design, it is not intended to transfer data from such a type of card reader to a computer or any other electronic device. Moreover, as smart cards having essentially the same widths as PCMCIA cards, this approach is not suited to be adapted to a PCMCIA smart card reader as bulky side walls of this prior art reader require more space as defined in the PCMCIA standards.
As it is becoming increasingly popular to use smart cards of different types for different purposes, it would be desirable to have a smart card reader assembly that can accommodate the associated different types of electronic circuitry and which conforms to the PCMCIA standards. Furthermore, it would be desirable to have a smart card reader assembly that is designed to adopt a plurality of different electronic circuits, especially electronic circuitry that is not vulnerable to external heat, inasmuch as thick film layers or hybrid circuitry containing surface mounted components can encounter weakened contacts after exposure to undue thermal influence.
Accordingly, it is an object of the invention to provide a smart card reader assembly for which no soldering, no welding and no thermal mounting operations, are necessary during manufacturing.
It is a further object of the invention to provide a smart card reader assembly for which a minimum amount of parts is necessary and that is able to be assembled manually as well as robotically.
A still further object of the invention is to provide a smart card reader assembly that can accommodate a variety of different electronic inserts.
The above objects are achieved with a smart card reader assembly comprising an upper housing unit having a first set of mounting means, and a lower housing unit having a second set of mounting means, said upper housing unit and said lower housing unit together defining a cavity for accommodating an electronic insert, said electronic insert comprising a receptacle connector for establishing electric contact with an associated electronic device and a contact array having terminals designed to mate with contact pads on a smart card upon insertion of the smart card into the portable smart card reader assembly, wherein upon mating said upper housing unit with said lower housing unit said first set of mounting means and said second set of mounting means are moved into locking engagement.
In a preferred embodiment, said first set of mounting means comprises at least one generally u-shaped lateral mounting flange and said second set of mounting means comprises at least one essentially inwardly inclined mounting flange to provide a mechanical snap-fit connection upon mating both housing units.
In another embodiment said at least one generally u-shaped lateral mounting flange is a laterally bent portion of an upper sheet metal cover of the upper housing unit and said at least one essentially inwardly inclined mounting flange is a laterally bent portion of a lower sheet metal cover of the lower housing unit, thus providing the necessary flexibility and rigidity for a snap-fit connection.
Preferably, said lower housing unit comprises a beveled dielectric front edge unit to facilitate insertion of the smart card into the reader assembly and precise and stable external dimensions are obtained if said upper housing unit defines laterally guiding flaps laterally engaging said beveled dielectric front edge unit of said lower housing unit upon mating of both housing units.
A convenient solution for guiding the smart card upon insertion without any lateral guiding element and a small and dense assembly is realized when said upper housing unit comprises a dielectric top cover extending spaced from and above the upper sheet metal cover and when said dielectric top cover and said upper sheet metal cover define a laterally open slot for inserting said smart card.
Additional rigidity in terms of shock and vibration resistance is obtained if said dielectric top cover further defines mounting portions for mounting lateral flaps of the lower sheet metal cover, said mounting portions comprising at least one longitudinal opening for press fit engagement of the lateral flaps of the lower sheet metal cover.
It is contemplated that the smart card reader assembly be manufactured according to the PCMCIA standards interface.